 /*
  * $Header: /cvshome/build/org.osgi.service.http/src/org/osgi/service/http/NamespaceException.java,v 1.11 2006/07/11 13:15:56 hargrave Exp $
  *
  * Copyright (c) OSGi Alliance (2000, 2006). All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 package org.osgi.service.http;

 /**
  * A NamespaceException is thrown to indicate an error with the caller's request
  * to register a servlet or resources into the URI namespace of the Http
  * Service. This exception indicates that the requested alias already is in use.
  *
  * @version $Revision: 1.11 $
  */
 public class NamespaceException extends Exception {
     static final long serialVersionUID = 7235606031147877747L;
     /**
      * Nested exception.
      */
     private final Throwable cause;

     /**
      * Construct a <code>NamespaceException</code> object with a detail message.
      *
      * @param message the detail message
      */
     public NamespaceException(String message) {
         super(message);
         cause = null;
     }

     /**
      * Construct a <code>NamespaceException</code> object with a detail message
      * and a nested exception.
      *
      * @param message The detail message.
      * @param cause The nested exception.
      */
     public NamespaceException(String message, Throwable cause) {
         super(message);
         this.cause = cause;
     }

     /**
      * Returns the nested exception.
      *
      * <p>This method predates the general purpose exception chaining mechanism.
      * The {@link #getCause()} method is now the preferred means of
      * obtaining this information.
      *
      * @return the nested exception or <code>null</code> if there is no nested
      * exception.
      */
     public Throwable getException() {
         return cause;
     }

     /**
      * Returns the cause of this exception or <code>null</code> if no
      * cause was specified when this exception was created.
      *
      * @return The cause of this exception or <code>null</code> if no
      * cause was specified.
      * @since 1.2
      */
     public Throwable getCause() {
         return cause;
     }

     /**
      * The cause of this exception can only be set when constructed.
      *
      * @param cause Cause of the exception.
      * @return This object.
      * @throws java.lang.IllegalStateException
      * This method will always throw an <code>IllegalStateException</code>
      * since the cause of this exception can only be set when constructed.
      * @since 1.2
      */
     public Throwable initCause(Throwable cause) {
         throw new IllegalStateException ();
     }
 }

